Picking up where Natus left off celebrating renewal and measurement of time, Sol Tempora chronicles phases of the sun. Of course the most romanticized and celebrated stage of the sun from our terrestrial vantage point is sunrise and sunset, when the filter of our atmosphere creates such pleasing color tones and glowing, observable warmth.
During sunrise and sunset, in normal conditions of atmospheric refraction, the sun's upper limb appears to be touching the horizon.
Civil twilight is the time after which city streetlights are lit, automobiles begin using headlights, in general, the time after which we begin to use artificial light.
Nautical twilight is the point where navigation via the horizon at sea is no longer possible. At this time, sailors can take reliable star sights of well-known stars, using a visible horizon for reference. The end of this period in the evening, or its beginning in the morning, is also the time at which traces of illumination near the sunset or sunrise point of the horizon are very difficult if not impossible to discern (this often being referred to as "first light" before civil dawn and "nightfall" after civil dusk). At the beginning of nautical twilight in the morning (nautical dawn), or at the end of nautical twilight in the evening (nautical dusk), under good atmospheric conditions and in the absence of other illumination, general outlines of ground objects may be distinguishable, but detailed outdoor operations are not possible, and the horizon is indistinct.
Astronomical twilight is the time when most casual observers would consider the entire sky already fully dark and is just beginning in the evening or just ending in the morning, and astronomers can easily make observations of point sources such as stars, but faint diffuse items such as nebulae and galaxies can only be properly observed beyond the limit of astronomical twilight. Theoretically, the dimmest stars ever visible to the naked eye-those of the sixth magnitude-will appear in the evening once the sun falls more than 18° below the horizon (i.e. when astronomical dusk occurs) and disappear when the sun moves to within 18° of the horizon in the morning (when astronomical dawn occurs). However, due to light pollution, some localities-generally those in large cities-may never have the opportunity to view even fourth-magnitude stars, irrespective of the presence of any twilight at all.
The length of twilight after sunset and before sunrise is heavily influenced by the latitude of the observer. In the Arctic and Antarctic regions, twilight (if at all) can last for several hours. There is no civil twilight at the poles within a month on either side of the winter solstice. At the poles, civil twilight can be as long as two weeks, while at the equator, it can go from day to night in as little as twenty minutes. This is because at low latitudes the sun's apparent movement is perpendicular to the observer's horizon. As one gets closer to the Arctic and Antarctic circles, the sun's disk moves toward the observer's horizon at a lower angle. The observer's earthly location will pass through the various twilight zones less directly, taking more time.
This new collection of slow building dub techno tracks consists of over five hours of pulse driven droning chords to bask in the warm thoughts of the observable phases of the sun.
See also:
downscope.bandcamp.com/album/natus
released October 20, 2020
Music by Rimas Campe
Cover photo by Joaquim Alves Gaspar
© 2020 alternating.bit music